A new flu vaccine which is injected into the skin instead of into muscle has recently been approved by the Food and Drug Administration for vaccination of the general population including patients with atopic dermatitis. This new vaccine has been shown to work as well as the vaccine which is injected into muscle when tested in people without atopic dermatitis. The main purpose of this study is to compare how people with atopic dermatitis respond to this new flu vaccine compared to non-atopic volunteers without atopic dermatitis. The second purpose is to look at how people with atopic dermatitis respond to the new vaccine which is injected into the skin compared to the vaccine which is injected into muscle.